Project/Area Number |
08680378
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Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
計算機科学
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Research Institution | HIROSHIMA CITY UNIVERSITY |
Principal Investigator |
NAKAMURA Yasuaki HIROSHIMA CITY UNIVERSITY,DEPARTMENT OF COMPUTER SCIENCE,PROFESSOR, 情報科学部, 教授 (10264946)
|
Co-Investigator(Kenkyū-buntansha) |
UCHIDA Tomoyuki HIROSHIMA CITY UNIVERSITY,DEPARTMENT OF COMPUTER SCIENCE,ASSOCIATE PROFESSOR, 情報科学部, 助教授 (70264934)
|
Project Period (FY) |
1996 – 1998
|
Project Status |
Completed (Fiscal Year 1998)
|
Budget Amount *help |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1998: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1997: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1996: ¥1,600,000 (Direct Cost: ¥1,600,000)
|
Keywords | DATA STRUCTURE / VIRTUAL REALITY / DABABAS / COMPUTER GRAPHICS / WALKTHROUGH / 3D VIRTUAL WORLD / GEOGRAPHIC INFORMATION SYSTEMS / IMAGE RETRIEVAL / 地図 / 仮想世界 / データ構造 / 3次元 |
Research Abstract |
To construct a large scale virtual space, a large number of spatial objects should be managed efficiently. In our project, an efficient hierarchical spatio-temporal data structure, called the PMD-tree, has been developed in 1996. The PMD-tree can manage the spatio-temporal data efficiently by preserving only the differences among the growing processes of a PMD-tree. Spatial temporal searches with time and spatial intervals can be performed quickly In 1997, the method for constructing spatial objects in a virtual world using a map were proposed. In a map, top views of objects in a three dimensional space are drawn as polygons or line segments. If picture with any view direction taken from arbitrary positions are given, a scene of 3D space can be obtained by selecting the picture taken from a given view point and view direction. In our method, a scene for a given view point and view direction is constructed from an plural pictures. When a view point and a direction are given, objects in the view volume are searhed using a map. Then pictures in which the objects are contained are found. The most appropriate parts of pictures are selected and applied the projective transformation. In 1998, a spatio-temporal data management method for moving objects was proposed. The PMD-tree was expanded and an new idea of time space bounding box (TSBB) was introduced.
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